CINCINNATI—A
therapy known to improve arm function in stroke patients actually works
by forcing the brain to “rewire” itself, say UC researchers.

A study led by Stephen Page, PhD, and published in the August 2006 issue of Archives of Physical Medicine and Rehabilitation,
reports that when stroke patients participate in modified
constraint-induced movement therapy, or mCIMT, areas of their brain
normally used for other functions are “recruited” to help move the
affected arm.

Patients
in the study were offered 10 weeks of mCIMT, in which restraint of the
unaffected arm forced them to use their affected arm for everyday
tasks.

Study
participants were given 30-minute therapy sessions three times a week.
They were asked to follow up at home, still using only their affected
arm for five hours each day, five days a week.

“Previous
studies have shown that mCIMT can improve arm function in patients, but
we weren’t quite sure how it was working,” says Page, assistant
professor and director of research in the department of physical
medicine and rehabilitation. “The cool thing about this study is that
we now know the mechanism.”

That
mechanism, referred to by the researchers as cortical reorganization,
was confirmed through functional magnetic resonance imaging (fMRI)
scans of the participants at the beginning and end of the study.

In
patients who benefited from constraint therapy, says Page, fMRI scans
clearly show activity in brain areas that weren’t active at the start
of the study

“To
our knowledge,” says Page, “this is the first study showing this kind
of ‘rewiring.’ We think it’s particularly important to stroke patients,
because this particular outpatient therapy is often covered by
insurance providers, so it’s quite accessible.”